Listen-before-talk for uplink transmissions using multiple subbands

ABSTRACT

Methods, systems, and devices for wireless communications are described that support listen before talk (LBT) for uplink transmissions using multiple subbands. A base station may support communication with a user equipment (UE) via multiple subbands and may transmit an uplink grant to the UE that allocates resources of the multiple subbands for transmission of a shared data channel by the UE. The base station may include an indication within the uplink grant that indicates to the UE to perform a given type of LBT for each subband. After transmitting the uplink grant, the base station may transmit control information or other signaling (e.g., channel occupancy time system information (COT-SI)) that indicates subbands on which the UE is to perform a given type of LBT or other subbands on which the UE is to perform a different type of LBT.

CROSS REFERENCE

The present Application for Patent claims the benefit of IndianProvisional Patent Application No. 201941033078 by BHATTAD et al.,entitled “LISTEN-BEFORE-TALK FOR UPLINK TRANSMISSIONS USING MULTIPLESUBBANDS,” filed Aug. 16, 2019, assigned to the assignee hereof, andexpressly incorporated by reference herein.

FIELD OF TECHNOLOGY

The following relates generally to wireless communications and morespecifically to listen before talk (LBT) for uplink transmissions usingmultiple subbands.

BACKGROUND

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonalfrequency division multiplexing (DFT-S-OFDM). A wireless multiple-accesscommunications system may include a number of base stations or networkaccess nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

In an unlicensed spectrum of a wireless communications system, wirelessdevices may implement an LBT procedure to monitor a channel on a subbandprior to communicating using that subband. If the subband is occupied,the wireless device may wait a duration of time and monitor the channelagain to see if it is occupied. If there are multiple subbands, however,the wireless device may not have sufficient time to perform LBT on allthe subbands, or the device may not be capable of performing LBT on allthe subbands, before preparing a transmission via the multiple subbands.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support listen before talk (LBT) for uplinktransmissions using multiple subbands. According to some aspects, a basestation may support communication with a user equipment (UE) viamultiple subbands and may transmit an uplink grant to the UE thatallocates resources of the multiple subbands for transmission of ashared data channel by the UE. The base station may include anindication within the uplink grant that indicates to the UE to perform agiven type of LBT for each subband. After transmitting the uplink grant,the base station may transmit control information or other signaling(e.g., channel occupancy time (COT) system information (COT-SI)) thatindicates subbands on which the UE is to perform a given type of LBT orother subbands on which the UE is to perform a different type of LBT.For example, depending on the capabilities of the UE, the UE may performa category 4 LBT procedure, which involves monitoring the subband,transmitting a request to send message, receiving a clear to sendmessage, and transmitting an uplink transmission if the subband isunoccupied. In other examples, the UE may perform a category 2 LBTprocedure, which involves monitoring the subband and transmitting achannel occupancy signal indicating that the UE is using or will use thesubband.

In some examples, the UE may perform a category 2 LBT in subbands wherethe UE knows the base station has the COT and already occupies thosesubbands, and a category 4 LBT on the subbands where the base stationdoes not already occupy the subbands. The UE may puncture or notpuncture based on the outcomes of the category 2 or 4 LBT procedures.

The base station may transmit an uplink grant to the UE for the sameuplink shared data channel over multiple subbands when the base stationis unsure of subband information at the time of sending the uplinkgrant. The UE may combine resource allocations from the multiple uplinkgrants to determine the resource allocation for the uplink shared datachannel. In some cases, the uplink shared data channel may include(e.g., may be multiplexed with) uplink control information (UCI) toavoid confusion between the base station and UE as to which subbands arebeing used for the uplink shared data channel.

A method of wireless communications at a UE is described. The method mayinclude identifying a set of subbands supported by a base station incommunication with the UE, receiving an uplink grant for transmission ofan uplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof a first type for the subset of the set of subbands in thetransmission time interval, receiving, after receiving the uplink grantand within the transmission time interval, signaling that indicates oneor more subbands of the subset associated with an LBT procedure of asecond type, and performing LBT procedures of the first type or thesecond type on the subset of the set of subbands based on the uplinkgrant and the signaling.

An apparatus for wireless communications at a UE is described. Theapparatus may include a processor, memory coupled with the processor,and instructions stored in the memory. The instructions may beexecutable by the processor to cause the apparatus to identify a set ofsubbands supported by a base station in communication with the UE,receive an uplink grant for transmission of an uplink shared datachannel via a subset of the set of subbands in a transmission timeinterval, the uplink grant indicating an LBT procedure of a first typefor the subset of the set of subbands in the transmission time interval,receive, after receiving the uplink grant and within the transmissiontime interval, signaling that indicates one or more subbands of thesubset associated with an LBT procedure of a second type, and performLBT procedures of the first type or the second type on the subset of theset of subbands based on the uplink grant and the signaling.

Another apparatus for wireless communications at a UE is described. Theapparatus may include means for identifying a set of subbands supportedby a base station in communication with the UE, receiving an uplinkgrant for transmission of an uplink shared data channel via a subset ofthe set of subbands in a transmission time interval, the uplink grantindicating an LBT procedure of a first type for the subset of the set ofsubbands in the transmission time interval, receiving, after receivingthe uplink grant and within the transmission time interval, signalingthat indicates one or more subbands of the subset associated with an LBTprocedure of a second type, and performing LBT procedures of the firsttype or the second type on the subset of the set of subbands based onthe uplink grant and the signaling.

A non-transitory computer-readable medium storing code for wirelesscommunications at a UE is described. The code may include instructionsexecutable by a processor to identify a set of subbands supported by abase station in communication with the UE, receive an uplink grant fortransmission of an uplink shared data channel via a subset of the set ofsubbands in a transmission time interval, the uplink grant indicating anLBT procedure of a first type for the subset of the set of subbands inthe transmission time interval, receive, after receiving the uplinkgrant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type, and perform LBT procedures of the first typeor the second type on the subset of the set of subbands based on theuplink grant and the signaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for puncturing the uplinkshared data channel on at least one subband based on an unsuccessful LBTprocedure for the at least one subband, and transmitting the uplinkshared data channel via the subset of the set of subbands excluding theat least one subband based on the puncturing.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing LBTprocedures of the second type on the one or more subbands of the subsetbased on the signaling, and transmitting the uplink shared data channelvia each of the one or more subbands associated with a successful LBTprocedure of the second type.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the uplinkshared data channel via the one or more subbands if each of the one ormore subbands may be associated with a successful LBT procedure of thesecond type, where the uplink shared data channel may be rate matched onthe one or more subbands.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing LBTprocedures of the first type on a first subband of the subset based onthe uplink grant, performing LBT procedures of the second type on asecond subband of the subset based on the signaling, and transmittingthe uplink shared data channel via each of the first and second subbandsassociated with a successful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing LBTprocedures of the first type on a first subband of the subset based onthe uplink grant, performing LBT procedures of the second type on asecond subband of the subset based on the signaling, and transmittingthe uplink shared data channel via the first and second subbands if thefirst and second subbands may be associated with a successful LBTprocedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing LBTprocedures of the first type on the subset of the set of subbands basedon the uplink grant and a capability of the UE, and transmitting theuplink shared data channel via each subband of the subset associatedwith a successful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the uplinkshared data channel via the subset of the set of subbands if each of thesubset may be associated with the successful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for dropping the uplinkshared data channel based on an unsuccessful LBT procedure on at leastone subband of the subset.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving multipleuplink grants via respective subbands of the subset of the set ofsubbands, where each of the multiple uplink grants includes resourceallocation information for the uplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the multiple uplinkgrants includes the same resource allocation information for the uplinkshared data channel via the respective subbands.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the multiple uplinkgrants includes different resource allocation information for the uplinkshared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining at leastone subband of the subset for transmission of the uplink shared datachannel based on the multiple uplink grants, where the at least onesubband corresponds to a subband over which one of the multiple uplinkgrants may be received.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the uplinkshared data channel via the at least one subband, where the uplinkshared data channel include UCI indicate the at least one subband usedfor transmission of the uplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the uplink grant includes aconfidence indicator that indicates puncturing information for thesubset of the set of subbands.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the confidence indicatorindicates which of the subset of the set of subbands may be availablefor the uplink shared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for preparing the uplinkshared data channel for transmission to the base station via the subsetof the set of subbands, puncturing the uplink shared data channel on theone or more subbands based on the signaling being received afterpreparing the uplink shared data channel for transmission, andtransmitting, based on the puncturing, the uplink shared data channelvia the subset of the set of subbands associated with a successful LBTprocedure and excluding the one or more subbands, where the uplinkshared data channel includes UCI indicating the subset of the set ofsubbands associated with the successful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving controlinformation indicating to the UE to include UCI with the uplink shareddata channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the control informationincludes RRC information or DCI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the UCI includes subbandsover which a punctured uplink shared data channel may be transmitted orsubbands used for transmission of the uplink shared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the uplinkshared data channel via each subband of the subset associated with asuccessful LBT procedure, where the uplink shared data channel includesUCI indicating each subband of the subset associated with the successfulLBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a set ofresources of each subband for the UCI, where the set of resources may bebased on one or more subbands of the subset subject to puncturingaccording to an unsuccessful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for evenly distributing UCIacross each subband, where the UCI includes information other thaninformation indicating each subband of the subset associated with thesuccessful LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining a set ofresources of each subband for the UCI based on a number of the subset ofthe set of subbands indicated in the uplink grant, a number of subbandsused for transmission of the uplink shared data channel, a number ofsubbands associated with the LBT procedure of the second type, all ofthe set of subbands supported by the base station for communicationswith the UE, or any combination thereof.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for multiplexing UCI withthe uplink shared data channel via at least one subband independent of anumber of subbands used for transmission of the uplink shared datachannel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a same number of symbols forthe at least one subband may be used for multiplexing the UCIirrespective of other subbands.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for preparing the uplinkshared data channel for transmission to the base station via the subsetof the set of subbands associated with a successful LBT procedure basedon the signaling, where the signaling may be received before a thresholdtime for preparation of the uplink shared data channel, and transmittingthe prepared uplink shared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the signalingafter a threshold time for preparation of the uplink shared datachannel, and transmitting the uplink shared data channel irrespective ofthe signaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the signalingafter a threshold time for preparation of the uplink shared datachannel, and dropping the uplink shared data channel based on thesignaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the signalingafter a threshold time for preparation of the uplink shared datachannel, puncturing the uplink shared data channel via the one or moresubbands indicated by the signaling, and transmitting the uplink shareddata channel via the subset of the set of subbands excluding the one ormore subbands based on the puncturing.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the LBT procedure of thefirst type includes a category 4 LBT procedure, and the LBT procedure ofthe second type includes a category 2 LBT procedure.

A method of wireless communications at a base station is described. Themethod may include identifying a set of subbands supported by the basestation in communication with a UE, transmitting an uplink grant for anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof the first type for the subset of the set of subbands in thetransmission time interval, performing an LBT procedure for each of thesubset of the set of subbands, and transmitting, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure.

An apparatus for wireless communications at a base station is described.The apparatus may include a processor, memory coupled with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to identify a setof subbands supported by the base station in communication with a UE,transmit an uplink grant for an uplink shared data channel via a subsetof the set of subbands in a transmission time interval, the uplink grantindicating an LBT procedure of the first type for the subset of the setof subbands in the transmission time interval, perform an LBT procedurefor each of the subset of the set of subbands, and transmit, aftertransmitting the uplink grant and within the transmission time interval,signaling that indicates one or more subbands of the subset associatedwith an LBT procedure of a second type based on performing the LBTprocedure.

Another apparatus for wireless communications at a base station isdescribed. The apparatus may include means for identifying a set ofsubbands supported by the base station in communication with a UE,transmitting an uplink grant for an uplink shared data channel via asubset of the set of subbands in a transmission time interval, theuplink grant indicating an LBT procedure of the first type for thesubset of the set of subbands in the transmission time interval,performing an LBT procedure for each of the subset of the set ofsubbands, and transmitting, after transmitting the uplink grant andwithin the transmission time interval, signaling that indicates one ormore subbands of the subset associated with an LBT procedure of a secondtype based on performing the LBT procedure.

A non-transitory computer-readable medium storing code for wirelesscommunications at a base station is described. The code may includeinstructions executable by a processor to identify a set of subbandssupported by the base station in communication with a UE, transmit anuplink grant for an uplink shared data channel via a subset of the setof subbands in a transmission time interval, the uplink grant indicatingan LBT procedure of the first type for the subset of the set of subbandsin the transmission time interval, perform an LBT procedure for each ofthe subset of the set of subbands, and transmit, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for monitoring each subbandof the subset for the uplink shared data channel from the UE aftertransmitting the signaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving the uplinkshared data channel via at least one subband of the subset, the uplinkshared data channel including UCI that indicates subbands of the subsetover which the uplink shared data channel may be transmitted orpunctured.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the UCI includes subbandsover which a punctured uplink shared data channel may be transmitted orsubbands used for transmission of the uplink shared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting multipleuplink grants via respective subbands of the subset of the set ofsubbands, where each of the multiple uplink grants includes resourceallocation information for the uplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the multiple uplinkgrants includes the same resource allocation information for the uplinkshared data channel via the respective subbands.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, each of the multiple uplinkgrants includes different resource allocation information for the uplinkshared data channel.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting controlinformation to the UE that indicates to the UE to include UCI with theuplink shared data channel.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the control informationincludes RRC information or DCI.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for monitoring multiplehypothesis for UCI from the UE based on the UE and the base stationbeing out of sync.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system thatsupports listen before talk (LBT) for uplink transmissions usingmultiple subbands in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a timeline that supports LBT for uplinktransmissions using multiple subbands in accordance with aspects of thepresent disclosure.

FIGS. 4A and 4B illustrate examples of channel occupancies that supportLBT for uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

FIG. 5 illustrates an example of a process flow that supports LBT foruplink transmissions using multiple subbands in accordance with aspectsof the present disclosure.

FIGS. 6 and 7 show block diagrams of devices that support LBT for uplinktransmissions using multiple subbands in accordance with aspects of thepresent disclosure.

FIG. 8 shows a block diagram of a communications manager that supportsLBT for uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

FIG. 9 shows a diagram of a system including a device that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

FIGS. 10 and 11 show block diagrams of devices that support LBT foruplink transmissions using multiple subbands in accordance with aspectsof the present disclosure.

FIG. 12 shows a block diagram of a communications manager that supportsLBT for uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

FIG. 13 shows a diagram of a system including a device that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

FIGS. 14 through 18 show flowcharts illustrating methods that supportLBT for uplink transmissions using multiple subbands in accordance withaspects of the present disclosure.

DETAILED DESCRIPTION

A base station may support multiple subbands in an unlicensed spectrumband for communications with a user equipment (UE). To utilize one ormore of the multiple subbands, the base station may perform a listenbefore talk (LBT) procedure on all the subbands to sense whether a givensubband is occupied (e.g., by other devices). During an LBT duration of9 μs, a base station may have 4 μs of sensing and 5 μs of processingprior to gaining access to the one or more subbands during a channeloccupancy time (COT). That is, the base station may have limited amountof time to determine if a given subband is available prior to winninguse of the subband for a COT. Further, once the LBT procedure iscomplete for a given subband, the base station may start to communicatewith a UE before another wireless device attempts to gain access to thesubband.

A base station may transmit an indication to a UE indicating whether thebase station is confident about a subband availability. The confidenceindication may specify if any data packets are to be punctured for anuplink shared data channel transmission in a given subband.

In some examples, the base station may send an uplink grant to a UE, butthe base station may be unable to confirm what type of LBT (e.g.,category 2 or category 4) is to be used on all the subbands. The basestation may include in the uplink grant whether the UE is to perform acategory 2 LBT (i.e., LBT including one-time channel sensing for a fixedperiod without a back-off period) or category 4 LBT (i.e., LBT with arandom (or other) back-off period and a variable sized contentionwindow). The base station may also send instruction in COT systeminformation (COT-SI) to specify which type of LBT the UE is to performfor one or more subbands of the multiple subbands.

In some examples, the UE may perform a category 2 LBT in subbands wherethe UE knows the base station has the COT and already occupies thosesubbands, and a category 4 LBT on the subbands where the base stationdoes not already occupy the subbands. The UE may puncture (e.g., chosenot to send an uplink shared data channel via a given subband) based onthe outcome of the category 2 or 4 LBT procedures on the multiplesubbands.

The base station may transmit an uplink grant to the UE for the samephysical uplink shared channel (PUSCH) over multiple subbands when thebase station is unsure of the subband information at the time of sendingthe uplink grant. The UE may combine all the resource allocation fromthe multiple grants to determine the resource allocation for the uplinkshared data channel. The uplink shared data channel transmission mayinclude uplink control information (UCI) to avoid confusion between thebase station and UE about which subbands are being used.

Aspects of the disclosure are initially described in the context ofwireless communications systems. Aspects are then described with respectto a timeline, channel occupancies, and a process flow. Aspects of thedisclosure are further illustrated by and described with reference toapparatus diagrams, system diagrams, and flowcharts that relate to LBTfor uplink transmissions using multiple subbands.

FIG. 1 illustrates an example of a wireless communications system 100that supports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. The wirelesscommunications system 100 may include base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A)network, an LTE-A Pro network, or a New Radio (NR) network. In somecases, the wireless communications system 100 may support enhancedbroadband communications, ultra-reliable (e.g., mission critical)communications, low latency communications, communications with low-costand low-complexity devices, or any combination thereof.

Base stations 105 may be dispersed throughout a geographic area to formthe wireless communications system 100 and may be devices in differentforms or having different capabilities. Base stations 105 and UEs 115may wirelessly communicate via one or more communication links 125. Eachbase station 105 may provide a coverage area 110 over which UEs 115 andthe base station 105 may establish communication links 125. The coveragearea 110 may be an example of a geographic area over which a basestation 105 and a UE 115 support the communication of signals accordingto one or more radio access technologies.

UEs 115 may be dispersed throughout a coverage area 110 of the wirelesscommunications system 100, and each UE 115 may be stationary, or mobile,or both at different times. UEs 115 may be devices in different forms orhaving different capabilities. Some example UEs 115 are illustrated inFIG. 1. The UEs 115 described herein may be able to communicate withvarious types of devices, such as other UEs 115, base stations 105,and/or network equipment (e.g., core network nodes, relay devices,integrated access and backhaul (IAB) nodes, or other network equipment),as shown in FIG. 1.

Base stations 105 may communicate with the core network 130, or with oneanother, or both. For example, base stations 105 may interface with thecore network 130 through backhaul links 120 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 120 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105), or indirectly(e.g., via core network 130), or both. In some examples, backhaul links120 may be or include one or more wireless links.

One or more of base stations 105 described herein may include or may bereferred to by a person of ordinary skill in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB orgiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, awireless device, a remote device, a handheld device, or a subscriberdevice, or some other suitable terminology, where the “device” may alsobe referred to as a unit, a station, a terminal, or a client, amongother examples. A UE 115 may also include or may be referred to as apersonal electronic device such as a cellular phone, a personal digitalassistant (PDA), a tablet computer, a laptop computer, or a personalcomputer. In some examples, a UE 115 may include or be referred to as awireless local loop (WLL) station, an Internet of Things (IoT) device,an Internet of Everything (IoE) device, a machine type communications(MTC) device, or the like, which may be implemented in various objectssuch as appliances, vehicles, meters, or the like.

The UEs 115 described herein may be able to communicate with varioustypes of devices, such as other UEs 115 that may sometimes act as relaysas well as base stations 105 and network equipment including macro eNBsor gNBs, small cell eNBs or gNBs, relay base stations, and the like, asshown in FIG. 1.

UEs 115 and base stations 105 may wirelessly communicate with oneanother via one or more communication links 125 over one or morecarriers. The term “carrier” may refer to a set of radio frequencyspectrum resources having a defined physical layer structure forsupporting communication links 125. For example, a carrier used for acommunication link 125 may include a portion of a radio frequencyspectrum band (e.g., a bandwidth part (BWP)) that is operated accordingto physical layer channels for a given radio access technology (e.g.,LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carryacquisition signaling (e.g., synchronization signals, systeminformation), control signaling that coordinates operation for thecarrier, user data, or other signaling. The wireless communicationssystem 100 may support communication with a UE 115 using carrieraggregation or multi-carrier operation. A UE 115 may be configured withmultiple downlink component carriers and one or more uplink componentcarriers according to a carrier aggregation configuration. Carrieraggregation may be used with both frequency division duplexing (FDD) andtime division duplexing (TDD) component carriers.

In some examples (e.g., in a carrier aggregation configuration), acarrier may also have acquisition signaling or control signaling thatcoordinates operations for other carriers. A carrier may be associatedwith a frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)) and may be positioned accordingto a channel raster for discovery by UEs 115. A carrier may be operatedin a standalone mode where initial acquisition and connection may beconducted by UEs 115 via the carrier, or the carrier may be operated ina non-standalone mode where a connection is anchored using a differentcarrier (e.g., of the same or a different radio access technology).

Communication links 125 shown in the wireless communications system 100may include uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions from a base station 105 to a UE 115. Carriers maycarry downlink or uplink communications (e.g., in an FDD mode) or may beconfigured to carry downlink and uplink communications (e.g., in a TDDmode).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80megahertz (MHz)). Devices of the wireless communications system 100(e.g., base stations 105, UEs 115, or both) may have hardwareconfigurations that support communications over a particular carrierbandwidth or may be configurable to support communications over one of aset of carrier bandwidths. In some examples, the wireless communicationssystem 100 may include base stations 105 and/or UEs 115 that supportsimultaneous communications via carriers associated with multiplecarrier bandwidths. In some examples, each served UE 115 may beconfigured for operating over portions (e.g., a sub-band, a BWP) or allof a carrier bandwidth.

Signal waveforms transmitted over a carrier may be made up of multiplesubcarriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)). In a system employing MCMtechniques, a resource element may consist of one symbol period (e.g., aduration of one modulation symbol) and one subcarrier, where the symbolperiod and subcarrier spacing are inversely related. The number of bitscarried by each resource element may depend on the modulation scheme(e.g., the order of the modulation scheme, the coding rate of themodulation scheme, or both). Thus, the more resource elements that a UE115 receives and the higher the order of the modulation scheme, thehigher the data rate may be for the UE 115. A wireless communicationsresource may refer to a combination of a radio frequency spectrumresource, a time resource, and a spatial resource (e.g., spatial layersor beams), and the use of multiple spatial layers may further increasethe data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, where anumerology may include a subcarrier spacing (Δf) and a cyclic prefix. Acarrier may be divided into BWPs having the same or differentnumerologies. In some examples, a UE 115 may be configured with multipleBWPs. In some cases, a single BWP for a carrier is active at a giventime, and communications for the UE 115 may be restricted to activeBWPs.

Time intervals for base stations 105 or UEs 115 may be expressed inmultiples of a basic time unit which may, for example, refer to asampling period of T_(S)=1/(Δf_(max)·N_(f)) seconds, where Δf_(max) mayrepresent the maximum supported subcarrier spacing, and N_(f) mayrepresent the maximum supported discrete Fourier transform (DFT) size.Time intervals of a communications resource may be organized accordingto radio frames each having a specified duration (e.g., 10 milliseconds(ms)). Each radio frame may be identified by a system frame number (SFN)(e.g., ranging from 0 to 1023).

Each frame may include multiple consecutively numbered subframes orslots, and each subframe or slot may have the same duration. In somecases, a frame may be divided (e.g., in the time domain) into subframes,and each subframe may be further divided into a number of slots.Alternatively, each frame may include a variable number of slots, andthe number of slots may depend on subcarrier spacing. Each slot mayinclude a number of symbol periods (e.g., depending on the length of thecyclic prefix prepended to each symbol period). In some wirelesscommunications systems 100, a slot may further be divided into multiplemini-slots containing one or more symbols. Excluding the cyclic prefix,each symbol period may contain one or more (e.g., N_(f)) samplingperiods. The duration of a symbol period may depend on the subcarrierspacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallestscheduling unit (e.g., in the time domain) of the wirelesscommunications system 100 and may be referred to as a transmission timeinterval (TTI). In some cases, the TTI duration (e.g., the number ofsymbol periods in a TTI) may be variable. Additionally or alternatively,the smallest scheduling unit of the wireless communications system 100may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. A control region (e.g., acontrol resource set (CORESET)) for a physical control channel may bedefined by a number of symbol periods and may extend across the systembandwidth or a subset of the system bandwidth of the carrier. One ormore control regions (e.g., CORESETs) may be configured for a set of UEs115. For example, UEs 115 may monitor or search control regions forcontrol information according to one or more search space sets, and eachsearch space set may include one or multiple control channel candidatesin one or more aggregation levels arranged in a cascaded manner. Anaggregation level for a control channel candidate may refer to a numberof control channel resources (e.g., control channel elements (CCEs))associated with encoded information for a control information formathaving a given payload size. Search space sets may include common searchspace sets configured for sending control information to multiple UEs115 and UE-specific search space sets for sending control information toa specific UE 115.

Each base station 105 may provide communication coverage via one or morecells, for example a macro cell, a small cell, a hot spot, or othertypes of cells, or various combinations thereof. The term “cell” mayrefer to a logical communication entity used for communication with abase station 105 (e.g., over a carrier) and may be associated with anidentifier for distinguishing neighboring cells (e.g., a physical cellidentifier (PCID), a virtual cell identifier (VCID), or others). In someexamples, a cell may also refer to a geographic coverage area 110 or aportion of a geographic coverage area 110 (e.g., a sector) over whichthe logical communication entity operates. Such cells may range fromsmaller areas (e.g., a structure, a subset of structure) to larger areasdepending on various factors such as the capabilities of the basestation 105. For example, a cell may be or include a building, a subsetof a building, exterior spaces between or overlapping with geographiccoverage areas 110, or the like.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider supporting themacro cell. A small cell may be associated with a lower-powered basestation 105, as compared with a macro cell, and a small cell may operatein the same or different (e.g., licensed, unlicensed) frequency bands asmacro cells. Small cells may provide unrestricted access to UEs 115 withservice subscriptions with the network provider or may providerestricted access to UEs 115 having an association with the small cell(e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associatedwith users in a home or office, and the like). A base station 105 maysupport one or multiple cells and may also support communications overthe one or more cells using one or multiple component carriers.

In some examples, a carrier may support multiple cells, and differentcells may be configured according to different protocol types (e.g.,MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), orothers) that may provide access for different types of devices.

In some examples, a base station 105 may be movable and thereforeprovide communication coverage for a moving geographic coverage area110. In some examples, different geographic coverage areas 110associated with different technologies may overlap, but the differentgeographic coverage areas 110 may be supported by the same base station105. In other examples, overlapping geographic coverage areas 110associated with different technologies may be supported by differentbase stations 105. The wireless communications system 100 may include,for example, a heterogeneous network in which different types of basestations 105 provide coverage for various geographic coverage areas 110using the same or different radio access technologies.

The wireless communications system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timings, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timings, andtransmissions from different base stations 105 may, in some examples,not be aligned in time. The techniques described herein may be used foreither synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay such information to acentral server or application program that makes use of the informationor presents the information to humans interacting with the applicationprogram. Some UEs 115 may be designed to collect information or enableautomated behavior of machines or other devices. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

The wireless communications system 100 may be configured to supportultra-reliable communications or low-latency communications, or variouscombinations thereof.

For example, the wireless communications system 100 may be configured tosupport ultra-reliable low-latency communications (URLLC) or missioncritical communications. UEs 115 may be designed to supportultra-reliable, low-latency, or critical functions (e.g., missioncritical functions). Ultra-reliable communications may include privatecommunication or group communication and may be supported by one or moremission critical services such as mission critical push-to-talk (MCPTT),mission critical video (MCVideo), or mission critical data (MCData).Support for mission critical functions may include prioritization ofservices, and mission critical services may be used for public safety orgeneral commercial applications. The terms ultra-reliable, low-latency,mission critical, and ultra-reliable low-latency may be usedinterchangeably herein.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 over a device-to-device (D2D) communication link 135(e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115utilizing D2D communications may be within the geographic coverage area110 of a base station 105. Other UEs 115 in such a group may be outsidethe geographic coverage area 110 of a base station 105 or be otherwiseunable to receive transmissions from a base station 105. In some cases,groups of UEs 115 communicating via D2D communications may utilize aone-to-many (1:M) system in which each UE 115 transmits to every otherUE 115 in the group. In some examples, a base station 105 facilitatesthe scheduling of resources for D2D communications. In other cases, D2Dcommunications are carried out between UEs 115 without the involvementof a base station 105.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC) or 5G core (5GC), which may include at leastone control plane entity that manages access and mobility (e.g., amobility management entity (MME), an access and mobility managementfunction (AMF)) and at least one user plane entity that routes packetsor interconnects to external networks (e.g., a serving gateway (S-GW), aPacket Data Network (PDN) gateway (P-GW), a user plane function (UPF)).The control plane entity may manage non-access stratum (NAS) functionssuch as mobility, authentication, and bearer management for UEs 115served by base stations 105 associated with the core network 130. UserIP packets may be transferred through the user plane entity, which mayprovide IP address allocation as well as other functions. The user planeentity may be connected to the network operators IP services 150. Theoperators IP services 150 may include access to the Internet,Intranet(s), an IP Multimedia Subsystem (IMS), or a Packet-SwitchedStreaming Service.

Some of the network devices, such as a base station 105, may includesubcomponents such as an access network entity 140, which may be anexample of an access node controller (ANC). Each access network entity140 may communicate with UEs 115 through a number of other accessnetwork transmission entities 145, which may be referred to as radioheads, smart radio heads, or transmission/reception points (TRPs). Eachaccess network transmission entity 145 may include one or more antennapanels. In some configurations, various functions of each access networkentity 140 or base station 105 may be distributed across various networkdevices (e.g., radio heads and ANCs) or consolidated into a singlenetwork device (e.g., a base station 105).

The wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features, but the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter ranges (e.g., less than 100 kilometers) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

The wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band, or in an extremely high frequency (EHF)region of the spectrum (e.g., from 30 GHz to 300 GHz), also known as themillimeter band. In some examples, the wireless communications system100 may support millimeter wave (mmW) communications between UEs 115 andbase stations 105, and EHF antennas of the respective devices may besmaller and more closely spaced than UHF antennas. In some cases, thismay facilitate use of antenna arrays within a device. The propagation ofEHF transmissions, however, may be subject to even greater atmosphericattenuation and shorter range than SHF or UHF transmissions. Techniquesdisclosed herein may be employed across transmissions that use one ormore different frequency regions, and designated use of bands acrossthese frequency regions may differ by country or regulating body.

The wireless communications system 100 may utilize both licensed andunlicensed radio frequency spectrum bands. For example, the wirelesscommunications system 100 may employ License Assisted Access (LAA),LTE-Unlicensed (LTE-U) radio access technology, or NR technology in anunlicensed band such as the 5 GHz industrial, scientific, and medical(ISM) band. When operating in unlicensed radio frequency spectrum bands,devices such as base stations 105 and UEs 115 may employ carrier sensingfor collision detection and avoidance. In some cases, operations inunlicensed bands may be based on a carrier aggregation configuration inconjunction with component carriers operating in a licensed band (e.g.,LAA). Operations in unlicensed spectrum may include downlinktransmissions, uplink transmissions, P2P transmissions, D2Dtransmissions, or the like.

A base station 105 or UE 115 may be equipped with multiple antennas,which may be used to employ techniques such as transmit diversity,receive diversity, multiple-input multiple-output (MIMO) communications,or beamforming. The antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays or antenna panels, which maysupport MIMO operations or transmit or receive beamforming. For example,one or more base station antennas or antenna arrays may be co-located atan antenna assembly, such as an antenna tower. In some cases, antennasor antenna arrays associated with a base station 105 may be located indiverse geographic locations. A base station 105 may have an antennaarray with a number of rows and columns of antenna ports that the basestation 105 may use to support beamforming of communications with a UE115. Likewise, a UE 115 may have one or more antenna arrays that maysupport various MIMO or beamforming operations. Additionally oralternatively, an antenna panel may support radio frequency beamformingfor a signal transmitted via an antenna port.

Base stations 105 or UEs 115 may use MIMO communications to exploitmultipath signal propagation and increase the spectral efficiency bytransmitting or receiving multiple signals via different spatial layers.Such techniques may be referred to as spatial multiplexing. The multiplesignals may, for example, be transmitted by the transmitting device viadifferent antennas or different combinations of antennas. Likewise, themultiple signals may be received by the receiving device via differentantennas or different combinations of antennas. Each of the multiplesignals may be referred to as a separate spatial stream and may carrybits associated with the same data stream (e.g., the same codeword) ordifferent data streams (e.g., different codewords). Different spatiallayers may be associated with different antenna ports used for channelmeasurement and reporting. MIMO techniques include single-user MIMO(SU-MIMO), where multiple spatial layers are transmitted to the samereceiving device, and multiple-user MIMO (MU-MIMO), where multiplespatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam, a receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that some signals propagatingat particular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude offsets, phase offsets, or both to signals carriedvia the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

The wireless communications system 100 may be a packet-based networkthat operates according to a layered protocol stack. In the user plane,communications at the bearer or Packet Data Convergence Protocol (PDCP)layer may be IP-based. A Radio Link Control (RLC) layer may performpacket segmentation and reassembly to communicate over logical channels.A Medium Access Control (MAC) layer may perform priority handling andmultiplexing of logical channels into transport channels. The MAC layermay also use error detection techniques, error correction techniques, orboth to support retransmissions at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical layer, transport channels may be mapped to physical channels.

UEs 115 and base stations 105 may support retransmissions of data toincrease the likelihood that data is received successfully. Hybridautomatic repeat request (HARQ) feedback is one technique for increasingthe likelihood that data is received correctly over a communication link125. HARQ may include a combination of error detection (e.g., using acyclic redundancy check (CRC)), forward error correction (FEC), andretransmission (e.g., automatic repeat request (ARQ)). HARQ may improvethroughput at the MAC layer in poor radio conditions (e.g., lowsignal-to-noise conditions). In some cases, a device may supportsame-slot HARQ feedback, where the device may provide HARQ feedback in aspecific slot for data received in a previous symbol in the slot. Inother cases, the device may provide HARQ feedback in a subsequent slot,or according to some other time interval.

Wireless communications system 100 may support communications between aUE 115 and a base station 105 using multiple subbands of an unlicensedspectrum. The base station 105 may transmit an initial grant to the UE115 for a shared data channel (e.g., a PUSCH, a physical downlink sharedchannel (PDSCH)) to be transmitted via the multiple subbands. Theinitial grant may include a confidence indicator that indicates whetherthe base station 105 is confident of the resource allocation included inthe initial grant. After the initial grant, the base station 105 maydetermine which of the subbands are available for communication of theshared data channel by performing LBT for each of the multiple subbands.The base station 105 may then transmit an indication of which of thesubbands are available for communication of the shared data channel withthe UE 115.

The UE 115 may receive an initial uplink grant from the base station 105for transmission of a shared data channel via multiple subbands of anunlicensed spectrum. The UE 115 may determine which of the multiplesubbands are available for communication by performing category 2 orcategory 4 LBT procedures for the multiple subbands. The determinationof which of the multiple subbands are available or punctured, the UE 115may use the confidence indicator from the base station 105 or otherfactors such as additional CAT-SI received after the initial grant thatindicates which of the subbands are available or punctured.

FIG. 2 illustrates an example of a wireless communications system 200that supports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. In some examples,wireless communications system 200 may implement aspects of wirelesscommunications system 100. As shown, wireless communications system 200includes base station 105-a and UE 115-a, which may be examples of thecorresponding devices described with reference to FIG. 1.

Base station 105-a may provide a coverage area 110-a within which UE115-a and base station 105-a may perform communications viacommunication links. The communication links may include one or morechannels of an unlicensed spectrum. In the unlicensed spectrum, one ormore channels may span or include multiple subbands 205, which may besupported by the base station 105-a for communications with the UE115-a. An LBT procedure may be performed (e.g., by a base station 105-a)to monitor if a given subband 205 is occupied. If the subband 205 isunoccupied, base station 105-a may use the subband 205 forcommunications with UE 115-a. As shown, the multiple subbands 205 mayinclude subbands 205-a, 205-b, 205-c, and 205-d.

In some examples, base station 105-a may send a confidence indicator 210(e.g., one or more bits of information related to a confidence level ofthe base station 105-a). The confidence indicator 210 may be included ina control channel (e.g., a physical downlink control channel (PDCCH))transmitted to the UE 115-a via one or more subbands 205. The confidenceindicator 210 may indicate whether the base station is confident aboutthe availability of one or more subbands 205 for a shared data channel(e.g., PUSCH, PDSCH) for the UE 115-a. Base station 105-a may indicatethe resource allocation or the confidence indicator 210 in DCI of thePDCCH, and the confidence indicator 210 may indicate whether the DCIincludes an actual assignment (e.g., base station 105-a is confidentabout the subband availability of the resource assignment) or an assumedassignment (e.g., the base station 105-a is not confident about thesubband availability of the resources assignment such that one or moresubbands 205 may be subject to puncturing).

In some examples, a confidence bit of 1 in subband 205-a may indicate toUE 115-a that no puncturing was done on the PDSCH transmitted viasubband 205-a or that no puncturing is to be performed by the UE 115-awhen transmitting PUSCH via subband 205-a. A confidence bit of 0 insubband 205-a may indicate to UE 115-a that base station 105-a is unsureif subband 205-a is available. This may be because at the time ofpreparing the PDCCH that includes the confidence bit, the base station105-a may not yet have performed LBT on the subband 205-a or may haveperformed LBT on the subband 205-a but may still be processing theresults of the LBT.

In some examples, subband usage may be in COT-SI or other controlinformation transmitted after an initial grant to the UE 115-a. Forexample, an initial grant transmitted by the base station 105-a mayinclude a confidence indicator 210 having a bit value of 0. Aftertransmitting the initial grant, the base station 105-a may transmitCOT-SI which may include a second confidence indicator 210 having a bitvalue of 1, which may indicate to the UE 115-a that the informationincluded in COT-SI is accurate (e.g., the information is based onsubband availability). In some cases, the confidence indicator 210 mayindicate that a given subband is subject to puncturing (e.g., the basestation 105-a may puncture a PDSCH transmission over the subband or theUE 115-a is to puncture the PUSCH transmission over the subband). COT-SImay be sent multiple times in a COT and may contain the confidence bitof 0 or 1 based on whether the base station 105-a has knowledge ofpuncturing of the PDSCH symbol in the subband.

The confidence bit may be included in the DCI associated with the PDCCHfrom the base station. The DCI may indicate to the UE whether the basestation is confident of subband information. A confidence bit of 1 inthe DCI may indicate that the UE may use category 2 LBT for all thesubbands. The DCI may indicate whether the UE should puncture anydownlink or uplink transmissions. The indication to puncture may bejointly coded with the confidence information 210 in the DCI. Basestation 105-a may transmit PDCCH with an uplink grant indicating validsubbands to UE 115-a.

In some examples, a base station may support various types of UEs. Atype of UE 115-a may not have puncturing capability and may perform acategory 2 or 4 LBT on all allocated subbands 205. If the LBT fails inany of the subbands 205, the UE 115-a may drop the whole data packet andnot transmit on the uplink transmission. The UE 115-a may only transmitif all the subbands 205 pass the LBT. Another type of UE 115-a maycreate data packets for all allocated subbands 205 and if any subbands205 fail the LBT, the UE 115-a may puncture the data packets in thosesubbands 205. In this way, the UE 115-a may still transmit even if theLBT failed on a subband 205.

FIG. 3 illustrates an example of a wireless communications system 300that supports techniques for LBT for uplink transmissions using multiplesubbands in accordance with various aspects of the present disclosure.In some examples, wireless communications system 300 may implementaspects of wireless communications system 100. As shown, wirelesscommunications system 300 includes base station 105-b and UE 115-b,which may be examples of the corresponding devices described withreference to FIGS. 1 and 2.

Base station 105-b and UE 115-b may be configured to communicate viasubbands 305-a, 305-b, 305-c, and 305-d of an unlicensed spectrum. Oncethe subbands 305 have been configured, base station 105-b and UE 115-bmay perform LBT procedures (e.g., category 2 LBT or category 4 LBT) toverify the availability of the subbands. LBT pass 310 may indicate thatsubbands 305-a, 305-b, and 305-d is available and LBT fail 315 mayindicate that subband 305-c is not available.

Base station 105-b may send uplink grant 325 to UE 115-b to indicate tothe UE 115-a to use category 2 or 4 LBT for all subbands 305. Basestation 105-b, upon gaining access to subbands 305-a, 305-b, and 305-dmay send COT-SI 320 containing subband information to UE 115-b. Basestation 105-b may instruct UE 115-b to use a category 2 LBT and begintransmission as base station 105-b has gained access to subbands 305-a,305-b, and 305-d. UE 115-b may receive the COT-SI 320 from base station105-b with instructions to use the category 2 LBT on subbands 305-a,305-b, and 305-c. For example, COT-SI 320 may indicate the subbands305-a, 305-b, and 305-d were acquired by base station 105-b. Further UE115-b may compare the COT-SI 320 with the uplink grant 325 and determineto use category 4 LBT before transmitting on subband 305-c, due to basestation 105-b not gaining access to subband 305-c. Before PUSCH 330, UE115-b may use category 2 LBT for the subbands 305 when base station105-b has the COT and category 4 LBT for the subbands base station 105-bdoes not have the COT.

In some examples, UE 115-b may prepare PUSCH 330 packets for allallocated subbands 305-a, 305-b, 305-c, and 305-d. UE 115-b may puncturePUSCH 330 transmissions on subband 305-c if LBT fails 315. UE 115-b mayperform a category 2 LBT on subbands 305-a, 305-b, and 305-d since UE115-b knows base station 105-b has access to those subbands, and mayonly transmit if the subbands pass the category 2 LBT. In some cases,depending on UE capability, UE 115-b may not attempt to transmit onsubband 305-c as base station 105-b does not have access to subband305-c. In some cases, UE 115-b may try a combination of category 2 and 4LBT procedures and transmit on the subbands where the LBT passes 310. Inother cases, UE 115-b may use category 4 LBT on all subbands 305-a,305-b, 305-c, and 305-d, and transmit over the those that the LBT passes310. UE 115-b may include a UCI 335 with one or more PUSCHs 330 toindicate to base station 105-b that transmission data on subband 305-cwas punctured or that transmission of PUSCH 330 was attempted onsubbands 305-a, 305-b, and 305-d. The UCI 335 may be multiplexed withthe PUSCH 330.

In some examples, UE 115-b may not have the ability to puncturetransmissions in subbands. UE 115-b may only use category 2 LBT or onlyuse category 4 LBT on subbands 305-a, 305-b, and 305-d, which basestation 105-b has gained access. UE 115-b may rate match to subbands305-a, 305-b, and 305-d and only transmit if all of subbands 305-a,305-b, and 305-d pass LBT. UE 115-b may include UCI 335 with PUSCH 330to indicate to base station 105-b on which subbands the UE 115-a istransmitting. UE 115-b may implement a combination of category 2 and 4LBT on all subbands 305-a, 305-b, 305-c, and 305-d, and transmit if allthe subbands 305 pass the LBT. If the LBT fails 315 for any of thesesubbands (e.g., subband 305-d), UE 115-b may drop the packet. Basestation 105-b and UE 115-b may both perform an LBT procedure to seewhich subbands 305 are available. If both the LBT procedures producethat subband 305-c is unavailable, then there is no issue with UE 115-bpuncturing the PUSCH 330. In some cases, UE 115-b may have to puncturethe PUSCH 330 transmission in subband 305-c if the subband informationis not received at the UE 115-b before the PUSCH 330 transmission. UE115-b may inform base station 105-b about puncturing the PUSCH 330transmission in subband 305-c.

In some examples, base station 105-b may send to UE 115-b uplink grant325 for the same PUSCH 330 over subbands 305-a, 305-b, 305-c, and 305-d,when base station 105-b is unsure of subband information at the time ofsending uplink grant 325. The uplink grants may be identical or may havedifferences in resource allocation. UE 115-b may combine all the grantsto determine the resource allocation. The uplink grants may includeresource allocation information for each of the subbands 305-a, 305-b,305-c, and 305-d and UE 115-b has to determine which subbands 305 to usefor PUSCH 330 transmission after performing LBT on each of the subbands305 or based on which subbands 305 the UE 115-b detected the uplinkgrants. UE 115-b may send UCI 335 along with the PUSCH 330, and the UCI335 may indicate the subbands 305 used for transmission of the PUSCH330.

In some examples, the PUSCH 330 transmission may include UCI 335 whenthere is a chance of confusion between base station 105-b and UE 115-babout which subbands are being used. UCI 335 may be included implicitlybased on a chance of confusion, or can be explicitly enabled controlinformation (e.g., via RRC or DCI). For example, the base station 105-bmay transmit an RRC message or may include information in DCI thatindicates to the UE 115-b to include UCI 335 with the PUSCH 330. In somecases, UCI 335 may include information about which subbands 305 on whichUE 115-b attempted transmission of the PUSCH 330 or which subbands PUSCH330 is transmitted. Base station 105-b may monitor 340 the subbands 305for the PUSCH 330.

In some cases, resource elements (REs) used for the UCI 335 may be afunction of whether UE 115-b may be allowed to puncture the PUSCH 330.The UCI multiplexing rules in may lead to the UCI bits being spreadequally across all subbands 305-a, 305-b, 305-c, and 305-d. For example,UCI multiplexing is such that the modulation may occur and rate matchingmay be performed on the number of REs that UE 115-b is using fortransmission. In some cases, this may apply to all UCI 335 and is notlimited to subband information of the UCI 335.

In some examples, base station 105-b may become unaware of whichsubbands UE 115-b is attempting to transmit on and how the UCI 335 ismultiplexed. Base station 105-b may become aware based on UE 115-b andbase station 105-b being in synchronization and the UCI multiplexing maybe based on the allocated subbands in the uplink grant 325. When basestation 105-b and UE 115-b are not in synchronization, base station105-b may learn of the UCI multiplexing based on the subbands 305 onwhich UE 115-b attempts to transmit the PUSCH 330. The UCI 335 may bemultiplexed only on subbands 305 which UE 115-b performs category 2 LBT(and LBT passes 310).

In some cases, base station 105-b may monitor hypothesis to determinewhich subbands 305 were used by UE 115-b for transmission. Multiplehypothesis may include base station 105-b testing each subband 305 todetermine if UE 115-b is using the subband 305. UCI 335 may assume alarger set of subbands that both base station 105-b and UE 115-b are insync on (e.g., all subbands, all allocated subbands) but only subset ofthese subbands may be considered by UE 115-b for transmission. In UCImultiplexing the same modulations symbols for UCI may be sent in aparticular subband independent of how many subbands UE 115-b attempts totransmit on.

FIG. 4A and FIG. 4B illustrate an example of channel occupancies 400that supports techniques for LBT for uplink transmissions using multiplesubbands in accordance with various aspects of the present disclosure.

In FIG. 4A, a UE may send a PUSCH 420 to a base station during COT 405.The base station may send uplink grant 415 before subband information isavailable at the base station. The UE may not know the valid COT-SI 425before transmitting PUSCH 420 to the base station. As a result, the UEmay perform an LBT on each of the subbands and may transmit the subbandsthat are available. The base station may transmit an invalid COT-SI 410and uplink grant 415 before PUSCH 420, and the valid COT-SI 425 once thebase station knows which subbands the base station has gained access. Insome cases, if the valid subband information is available faster thanthe PUSCH 420 preparation time, the UE may send PUSCH 420 on the correctsubband.

In FIG. 4B, the UE may send a PUSCH 420-a to a base station during COT405-a. The base station may send uplink grant 415-a before subbandinformation is available at the base station. In some cases, the basestation may transmit valid COT-SI 425-a before PUSCH 420-a istransmitted to the base station. As a result, the UE may perform an LBTof the subband and may transmit on the subband if it is available andmay determine the type of LBT to perform for each subband based on thevalid COT-SI 425-a. The base station may transmit an invalid COT-SI410-a and uplink grant 415-a before the valid COT-SI 425-a. In a firstcase, if the valid subband information is available after the PUSCH420-a preparation time and valid COT-SI 425-a is the same as the invalidCOT-SI 410, then the UE may transmit PUSCH 420-a already prepared. In asecond case, if the valid subband information is available after thePUSCH 420-a preparation time but valid COT-SI 425-a is the not the sameas the invalid COT-SI, then the UE may drop the already prepared PUSCH420-a. In a third case, if the valid subband information is availableafter the PUSCH 420-a preparation time but valid COT-SI 425-a is the notthe same as the invalid COT-SI, then the UE may puncture the alreadyprepared PUSCH 420-a and transmit to the base station.

FIG. 5 illustrates an example of a process flow 500 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. In some examples, process flow 500may implement aspects of wireless communication systems 100. or 200. Forexample, process flow 500 may include base station 105-c and UE 115-c,which may be examples of the corresponding devices described withreference to FIG. 1 or 2.

At 505, base station 105-c may identify a number of subbands which aresupported by base station 105-c in communication with UE 115-c. At 510,UE 115-c may identify a number of subbands which are supported by basestation 105-c in communication with UE 115-c. At 515, base station 105-cmay transmit an uplink grant for an uplink shared data channel via asubset of the identified subbands in a transmission time interval (TTI).The uplink grant may comprise a confidence indicator which indicatespuncturing information for the subset of subbands or which of the subsetof subbands is available for the uplink shared data channel. The uplinkgrant may indicate an LBT procedure (e.g., category 2 or category 4) forthe subset of identified subbands. Base station 105-c may transmitmultiple uplink grants including the same or different resourceallocation information for the uplink shared data channel. Base station105-c may transmit control information to UE 115-c that indicates to UE115-c to include UCI with the uplink shared data channel. Base station105-c may monitor for multiple hypothesis for UCI from UE 115-c based onbase station 105-c and UE 115-c being in sync.

At 520, base station 105-c may perform an LBT procedure for each of thesubset of identified subbands. At 525, base station 105-c may transmitsignaling that indicates subbands in the subset of subbands associatedwith the LBT procedure. Base station 105-c may monitor the subset ofsubbands for the uplink shared data channel transmission from the UE115-c.

At 530, UE 115-c may perform an LBT procedure on the subset of subbandsbased on the uplink grant from base station 105-c. UE 115-c may puncturethe uplink shared data channel on one of the subbands based on the LBTprocedure results. UE 115-c may drop the uplink shared data channelpassed on an unsuccessful LBT procedure on a subband of the subset. UE115-c may prepare the uplink shared data channel for transmission tobase station 105-c. At 535, UE 115-c may transmit the uplink shared datachannel via the subbands with successful LBT procedures. The uplinkshared data channel may be rate matched on one or more of the subbands.Base station 105-c may receive the uplink shared data channeltransmission via one or more of the subbands in the subset of subbands.The uplink control data channel transmission may include UCI whichindicates subbands of the subset of subbands over which the uplinkshared data channel is transmitted or punctured.

FIG. 6 shows a block diagram 600 of a device 605 that supports LBT foruplink transmissions using multiple subbands in accordance with aspectsof the present disclosure. The device 605 may be an example of aspectsof a UE 115 as described herein. The device 605 may include a receiver610, a communications manager 615, and a transmitter 620. The device 605may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to LBT foruplink transmissions using multiple subbands, etc.). Information may bepassed on to other components of the device 605. The receiver 610 may bean example of aspects of the transceiver 920 described with reference toFIG. 9. The receiver 610 may utilize a single antenna or a set ofantennas.

The communications manager 615 may identify a set of subbands supportedby a base station in communication with the UE, receive an uplink grantfor transmission of an uplink shared data channel via a subset of theset of subbands in a transmission time interval, the uplink grantindicating an LBT procedure of a first type for the subset of the set ofsubbands in the transmission time interval, receive, after receiving theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type, and perform LBT procedures of the first typeor the second type on the subset of the set of subbands based on theuplink grant and the signaling. The communications manager 615 may be anexample of aspects of the communications manager 910 described herein.

The communications manager 615, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 615, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The communications manager 615, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 615, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 615, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 620 may transmit signals generated by other componentsof the device 605. In some examples, the transmitter 620 may becollocated with a receiver 610 in a transceiver module. For example, thetransmitter 620 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The transmitter 620 may utilize asingle antenna or a set of antennas.

In some examples, the communications manager 615 may be implemented asan integrated circuit or chipset for a mobile device modem, and thereceiver 610 and transmitter 620 may be implemented as analog components(e.g., amplifiers, filters, antennas) coupled with the mobile devicemodem to enable wireless transmission and reception over one or morebands.

The communications manager 615 as described herein may be implemented torealize one or more potential advantages. One implementation may allowthe device 605 to determine LBT procedures to perform on one or moresubbands in an unlicensed spectrum. Based on the techniques for LBT, thedevice 605 may determine which type of LBT to perform for each ofmultiple subbands and, therefore, may perform more accurate LBTprocedures for each subband.

As such, the device 605 may increase the likelihood of accuratelysensing the occupancy of a channel and, accordingly, may communicateover the channel with a greater likelihood of successful communications.In some examples, based on a greater likelihood of successfulcommunications and the type of LBT procedure to be performed, the device605 may more efficiently power a processor or one or more processingunits associated with an LBT procedure and transmitting and receivingcommunications, which may enable the device to save power and increasebattery life.

FIG. 7 shows a block diagram 700 of a device 705 that supports LBT foruplink transmissions using multiple subbands in accordance with aspectsof the present disclosure. The device 705 may be an example of aspectsof a device 605, or a UE 115 as described herein. The device 705 mayinclude a receiver 710, a communications manager 715, and a transmitter740. The device 705 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

The receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to LBT foruplink transmissions using multiple subbands, etc.). Information may bepassed on to other components of the device 705. The receiver 710 may bean example of aspects of the transceiver 920 described with reference toFIG. 9. The receiver 710 may utilize a single antenna or a set ofantennas.

The communications manager 715 may be an example of aspects of thecommunications manager 615 as described herein. The communicationsmanager 715 may include a subband manager 720, an uplink grant receiver725, a signaling receiver 730, and an LBT component 735. Thecommunications manager 715 may be an example of aspects of thecommunications manager 910 described herein.

The subband manager 720 may identify a set of subbands supported by abase station in communication with the UE.

The uplink grant receiver 725 may receive an uplink grant fortransmission of an uplink shared data channel via a subset of the set ofsubbands in a transmission time interval, the uplink grant indicating anLBT procedure of a first type for the subset of the set of subbands inthe transmission time interval.

The signaling receiver 730 may receive, after receiving the uplink grantand within the transmission time interval, signaling that indicates oneor more subbands of the subset associated with an LBT procedure of asecond type.

The LBT component 735 may perform LBT procedures of the first type orthe second type on the subset of the set of subbands based on the uplinkgrant and the signaling.

The transmitter 740 may transmit signals generated by other componentsof the device 705. In some examples, the transmitter 740 may becollocated with a receiver 710 in a transceiver module. For example, thetransmitter 740 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The transmitter 740 may utilize asingle antenna or a set of antennas.

FIG. 8 shows a block diagram 800 of a communications manager 805 thatsupports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. The communicationsmanager 805 may be an example of aspects of a communications manager615, a communications manager 715, or a communications manager 910described herein. The communications manager 805 may include a subbandmanager 810, an uplink grant receiver 815, a signaling receiver 820, anLBT component 825, a puncture module 830, an uplink transmitter 835, adrop component 840, a subband component 845, a preparation module 850, acontrol receiver 855, and a resource manager 860. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

The subband manager 810 may identify a set of subbands supported by abase station in communication with the UE.

The uplink grant receiver 815 may receive an uplink grant fortransmission of an uplink shared data channel via a subset of the set ofsubbands in a transmission time interval, the uplink grant indicating anLBT procedure of a first type for the subset of the set of subbands inthe transmission time interval.

In some examples, receiving multiple uplink grants via respectivesubbands of the subset of the set of subbands, where each of themultiple uplink grants includes resource allocation information for theuplink shared data channel.

In some cases, each of the multiple uplink grants includes the sameresource allocation information for the uplink shared data channel viathe respective subbands.

In some cases, each of the multiple uplink grants includes differentresource allocation information for the uplink shared data channel.

In some cases, the uplink grant includes a confidence indicator thatindicates puncturing information for the subset of the set of subbands.

In some cases, the confidence indicator indicates which of the subset ofthe set of subbands is available for the uplink shared data channel.

The signaling receiver 820 may receive, after receiving the uplink grantand within the transmission time interval, signaling that indicates oneor more subbands of the subset associated with an LBT procedure of asecond type.

In some examples, the signaling receiver 820 may receive the signalingafter a threshold time for preparation of the uplink shared datachannel.

The LBT component 825 may perform LBT procedures of the first type orthe second type on the subset of the set of subbands based on the uplinkgrant and the signaling.

In some examples, the LBT component 825 may perform LBT procedures ofthe second type on the one or more subbands of the subset based on thesignaling.

In some examples, the LBT component 825 may perform LBT procedures ofthe first type on a first subband of the subset based on the uplinkgrant.

In some examples, the LBT component 825 may perform LBT procedures ofthe second type on a second subband of the subset based on thesignaling.

In some examples, the LBT component 825 may perform LBT procedures ofthe first type on the subset of the set of subbands based on the uplinkgrant and a capability of the UE.

In some cases, the LBT procedure of the first type includes a category 4LBT procedure.

In some cases, the LBT procedure of the second type includes a category2 LBT procedure.

The puncture module 830 may puncture the uplink shared data channel onat least one subband based on an unsuccessful LBT procedure for the atleast one subband.

In some examples, the puncture module 830 may puncture the uplink shareddata channel on the one or more subbands based on the signaling beingreceived after preparing the uplink shared data channel fortransmission.

In some examples, the puncture module 830 may puncture the uplink shareddata channel via the one or more subbands indicated by the signaling.

The uplink transmitter 835 may transmit the uplink shared data channelvia the subset of the set of subbands excluding the at least one subbandbased on the puncturing.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via each of the one or more subbands associated witha successful LBT procedure of the second type.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via the one or more subbands if each of the one ormore subbands is associated with a successful LBT procedure of thesecond type, where the uplink shared data channel is rate matched on theone or more subbands.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via each of the first and second subbands associatedwith a successful LBT procedure.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via the first and second subbands if the first andsecond subbands are associated with a successful LBT procedure.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via each subband of the subset associated with asuccessful LBT procedure.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via the subset of the set of subbands if each of thesubset is associated with the successful LBT procedure.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via the at least one subband, where the uplinkshared data channel include UCI indicate the at least one subband usedfor transmission of the uplink shared data channel.

In some examples, the uplink transmitter 835 may transmit, based on thepuncturing, the uplink shared data channel via the subset of the set ofsubbands associated with a successful LBT procedure and excluding theone or more subbands, where the uplink shared data channel includes UCIindicating the subset of the set of subbands associated with thesuccessful LBT procedure.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via each subband of the subset associated with asuccessful LBT procedure, where the uplink shared data channel includesUCI indicating each subband of the subset associated with the successfulLBT procedure.

In some examples, the uplink transmitter 835 may transmit the prepareduplink shared data channel.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel irrespective of the signaling.

In some examples, the uplink transmitter 835 may transmit the uplinkshared data channel via the subset of the set of subbands excluding theone or more subbands based on the puncturing.

In some cases, the UCI includes subbands over which a punctured uplinkshared data channel is transmitted or subbands used for transmission ofthe uplink shared data channel.

The drop component 840 may drop the uplink shared data channel based onan unsuccessful LBT procedure on at least one subband of the subset.

In some examples, the drop component 840 may drop the uplink shared datachannel based on the signaling.

The subband component 845 may determine at least one subband of thesubset for transmission of the uplink shared data channel based on themultiple uplink grants, where the at least one subband corresponds to asubband over which one of the multiple uplink grants is received.

The preparation module 850 may prepare the uplink shared data channelfor transmission to the base station via the subset of the set ofsubbands.

In some examples, the preparation module 850 may prepare the uplinkshared data channel for transmission to the base station via the subsetof the set of subbands associated with a successful LBT procedure basedon the signaling, where the signaling is received before a thresholdtime for preparation of the uplink shared data channel.

The control receiver 855 may receive control information indicating tothe UE to include UCI with the uplink shared data channel.

In some cases, the control information includes RRC information or DCI.

The resource manager 860 may determine a set of resources of eachsubband for the UCI, where the set of resources is based on one or moresubbands of the subset subject to puncturing according to anunsuccessful LBT procedure.

In some examples, evenly distributing UCI across each subband, where theUCI includes information other than information indicating each subbandof the subset associated with the successful LBT procedure.

In some examples, the resource manager 860 may determine a set ofresources of each subband for the UCI based on a number of the subset ofthe set of subbands indicated in the uplink grant, a number of subbandsused for transmission of the uplink shared data channel, a number ofsubbands associated with the LBT procedure of the second type, all ofthe set of subbands supported by the base station for communicationswith the UE, or any combination thereof.

In some examples, the resource manager 860 may multiplex UCI with theuplink shared data channel via at least one subband independent of anumber of subbands used for transmission of the uplink shared datachannel.

In some cases, a same number of symbols for the at least one subband isused for multiplexing the UCI irrespective of other subbands.

FIG. 9 shows a diagram of a system 900 including a device 905 thatsupports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. The device 905 may bean example of or include the components of device 605, device 705, or aUE 115 as described herein. The device 905 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a communicationsmanager 910, an I/O controller 915, a transceiver 920, an antenna 925,memory 930, and a processor 940. These components may be in electroniccommunication via one or more buses (e.g., bus 945).

The communications manager 910 may identify a set of subbands supportedby a base station in communication with the UE, receive an uplink grantfor transmission of an uplink shared data channel via a subset of theset of subbands in a transmission time interval, the uplink grantindicating an LBT procedure of a first type for the subset of the set ofsubbands in the transmission time interval, receive, after receiving theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type, and perform LBT procedures of the first typeor the second type on the subset of the set of subbands based on theuplink grant and the signaling.

The I/O controller 915 may manage input and output signals for thedevice 905. The I/O controller 915 may also manage peripherals notintegrated into the device 905. In some cases, the I/O controller 915may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 915 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 915may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 915may be implemented as part of a processor. In some cases, a user mayinteract with the device 905 via the I/O controller 915 or via hardwarecomponents controlled by the I/O controller 915.

The transceiver 920 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 920 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 920may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas.

In some cases, the wireless device may include a single antenna 925.However, in some cases the device may have more than one antenna 925,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 930 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 930 may store computer-readable,computer-executable code 935 including instructions that, when executed,cause the processor to perform various functions described herein. Insome cases, the memory 930 may contain, among other things, a basic I/Osystem (BIOS) which may control basic hardware or software operationsuch as the interaction with peripheral components or devices.

The processor 940 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 940 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 940. The processor 940 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 930) to cause the device 905 to perform variousfunctions (e.g., functions or tasks supporting LBT for uplinktransmissions using multiple subbands).

The code 935 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 935 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 935 may not be directly executable by theprocessor 940 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 10 shows a block diagram 1000 of a device 1005 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The device 1005 may be an example ofaspects of a base station 105 as described herein. The device 1005 mayinclude a receiver 1010, a communications manager 1015, and atransmitter 1020. The device 1005 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 1010 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to LBT foruplink transmissions using multiple subbands, etc.). Information may bepassed on to other components of the device 1005. The receiver 1010 maybe an example of aspects of the transceiver 1320 described withreference to FIG. 13. The receiver 1010 may utilize a single antenna ora set of antennas.

The communications manager 1015 may identify a set of subbands supportedby the base station in communication with a UE, transmit an uplink grantfor an uplink shared data channel via a subset of the set of subbands ina transmission time interval, the uplink grant indicating an LBTprocedure of the first type for the subset of the set of subbands in thetransmission time interval, perform an LBT procedure for each of thesubset of the set of subbands, and transmit, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure. Thecommunications manager 1015 may be an example of aspects of thecommunications manager 1310 described herein.

The communications manager 1015, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1015, or itssub-components may be executed by a general-purpose processor, a DSP, anASIC, a FPGA or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 1015, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1015, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1015, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

The transmitter 1020 may transmit signals generated by other componentsof the device 1005. In some examples, the transmitter 1020 may becollocated with a receiver 1010 in a transceiver module. For example,the transmitter 1020 may be an example of aspects of the transceiver1320 described with reference to FIG. 13. The transmitter 1020 mayutilize a single antenna or a set of antennas.

FIG. 11 shows a block diagram 1100 of a device 1105 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The device 1105 may be an example ofaspects of a device 1005, or a base station 105 as described herein. Thedevice 1105 may include a receiver 1110, a communications manager 1115,and a transmitter 1140. The device 1105 may also include a processor.Each of these components may be in communication with one another (e.g.,via one or more buses).

The receiver 1110 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to LBT foruplink transmissions using multiple subbands, etc.). Information may bepassed on to other components of the device 1105. The receiver 1110 maybe an example of aspects of the transceiver 1320 described withreference to FIG. 13. The receiver 1110 may utilize a single antenna ora set of antennas.

The communications manager 1115 may be an example of aspects of thecommunications manager 1015 as described herein. The communicationsmanager 1115 may include a subband identifier 1120, an uplink granttransmitter 1125, an LBT module 1130, and a signaling transmitter 1135.The communications manager 1115 may be an example of aspects of thecommunications manager 1310 described herein.

The subband identifier 1120 may identify a set of subbands supported bythe base station in communication with a UE.

The uplink grant transmitter 1125 may transmit an uplink grant for anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof the first type for the subset of the set of subbands in thetransmission time interval.

The LBT module 1130 may perform an LBT procedure for each of the subsetof the set of subbands.

The signaling transmitter 1135 may transmit, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure.

The transmitter 1140 may transmit signals generated by other componentsof the device 1105. In some examples, the transmitter 1140 may becollocated with a receiver 1110 in a transceiver module. For example,the transmitter 1140 may be an example of aspects of the transceiver1320 described with reference to FIG. 13. The transmitter 1140 mayutilize a single antenna or a set of antennas.

FIG. 12 shows a block diagram 1200 of a communications manager 1205 thatsupports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. The communicationsmanager 1205 may be an example of aspects of a communications manager1015, a communications manager 1115, or a communications manager 1310described herein. The communications manager 1205 may include a subbandidentifier 1210, an uplink grant transmitter 1215, an LBT module 1220, asignaling transmitter 1225, a monitoring component 1230, an uplinkreceiver 1235, and a control transmitter 1240. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The subband identifier 1210 may identify a set of subbands supported bythe base station in communication with a UE.

The uplink grant transmitter 1215 may transmit an uplink grant for anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof the first type for the subset of the set of subbands in thetransmission time interval.

In some examples, transmitting multiple uplink grants via respectivesubbands of the subset of the set of subbands, where each of themultiple uplink grants includes resource allocation information for theuplink shared data channel.

In some cases, each of the multiple uplink grants includes the sameresource allocation information for the uplink shared data channel viathe respective subbands.

In some cases, each of the multiple uplink grants includes differentresource allocation information for the uplink shared data channel.

The LBT module 1220 may perform an LBT procedure for each of the subsetof the set of subbands.

The signaling transmitter 1225 may transmit, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure.

The monitoring component 1230 may monitor each subband of the subset forthe uplink shared data channel from the UE after transmitting thesignaling.

In some examples, the monitoring component 1230 may monitor multiplehypothesis for UCI from the UE based on the UE and the base stationbeing out of sync.

The uplink receiver 1235 may receive the uplink shared data channel viaat least one subband of the subset, the uplink shared data channelincluding UCI that indicates subbands of the subset over which theuplink shared data channel is transmitted or punctured.

In some cases, the UCI includes subbands over which a punctured uplinkshared data channel is transmitted or subbands used for transmission ofthe uplink shared data channel.

The control transmitter 1240 may transmit control information to the UEthat indicates to the UE to include UCI with the uplink shared datachannel.

In some cases, the control information includes RRC information or DCI.

FIG. 13 shows a diagram of a system 1300 including a device 1305 thatsupports LBT for uplink transmissions using multiple subbands inaccordance with aspects of the present disclosure. The device 1305 maybe an example of or include the components of device 1005, device 1105,or a base station 105 as described herein. The device 1305 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including acommunications manager 1310, a network communications manager 1315, atransceiver 1320, an antenna 1325, memory 1330, a processor 1340, and aninter-station communications manager 1345. These components may be inelectronic communication via one or more buses (e.g., bus 1350).

The communications manager 1310 may identify a set of subbands supportedby the base station in communication with a UE, transmit an uplink grantfor an uplink shared data channel via a subset of the set of subbands ina transmission time interval, the uplink grant indicating an LBTprocedure of the first type for the subset of the set of subbands in thetransmission time interval, perform an LBT procedure for each of thesubset of the set of subbands, and transmit, after transmitting theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure.

The network communications manager 1315 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1315 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1320 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1320 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1320 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1325.However, in some cases the device may have more than one antenna 1325,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1330 may include RAM, ROM, or a combination thereof. Thememory 1330 may store computer-readable code 1335 including instructionsthat, when executed by a processor (e.g., the processor 1340) cause thedevice to perform various functions described herein. In some cases, thememory 1330 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1340 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, the processor1340 may be configured to operate a memory array using a memorycontroller. In some cases, a memory controller may be integrated intoprocessor 1340. The processor 1340 may be configured to executecomputer-readable instructions stored in a memory (e.g., the memory1330) to cause the device 1305 to perform various functions (e.g.,functions or tasks supporting LBT for uplink transmissions usingmultiple subbands).

The inter-station communications manager 1345 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1345 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1345 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1335 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1335 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1335 may not be directly executable by theprocessor 1340 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 14 shows a flowchart illustrating a method 1400 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The operations of method 1400 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1400 may be performed by acommunications manager as described with reference to FIGS. 6 through 9.In some examples, a UE may execute a set of instructions to control thefunctional elements of the UE to perform the functions described herein.Additionally or alternatively, a UE may perform aspects of the functionsdescribed herein using special-purpose hardware.

At 1405, the UE may identify a set of subbands supported by a basestation in communication with the UE. The operations of 1405 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1405 may be performed by a subband manageras described with reference to FIGS. 6 through 9.

At 1410, the UE may receive an uplink grant for transmission of anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof a first type for the subset of the set of subbands in thetransmission time interval. The operations of 1410 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1410 may be performed by an uplink grant receiver asdescribed with reference to FIGS. 6 through 9.

At 1415, the UE may receive, after receiving the uplink grant and withinthe transmission time interval, signaling that indicates one or moresubbands of the subset associated with an LBT procedure of a secondtype. The operations of 1415 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1415may be performed by a signaling receiver as described with reference toFIGS. 6 through 9.

At 1420, the UE may perform LBT procedures of the first type or thesecond type on the subset of the set of subbands based on the uplinkgrant and the signaling. The operations of 1420 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1420 may be performed by an LBT component as describedwith reference to FIGS. 6 through 9.

FIG. 15 shows a flowchart illustrating a method 1500 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The operations of method 1500 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1500 may be performed by acommunications manager as described with reference to FIGS. 6 through 9.In some examples, a UE may execute a set of instructions to control thefunctional elements of the UE to perform the functions described herein.Additionally or alternatively, a UE may perform aspects of the functionsdescribed herein using special-purpose hardware.

At 1505, the UE may identify a set of subbands supported by a basestation in communication with the UE. The operations of 1505 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1505 may be performed by a subband manageras described with reference to FIGS. 6 through 9.

At 1510, the UE may receive an uplink grant for transmission of anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof a first type for the subset of the set of subbands in thetransmission time interval. The operations of 1510 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1510 may be performed by an uplink grant receiver asdescribed with reference to FIGS. 6 through 9.

At 1515, the UE may receive, after receiving the uplink grant and withinthe transmission time interval, signaling that indicates one or moresubbands of the subset associated with an LBT procedure of a secondtype. The operations of 1515 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1515may be performed by a signaling receiver as described with reference toFIGS. 6 through 9.

At 1520, the UE may perform LBT procedures of the first type or thesecond type on the subset of the set of subbands based on the uplinkgrant and the signaling. The operations of 1520 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1520 may be performed by an LBT component as describedwith reference to FIGS. 6 through 9.

At 1525, the UE may puncture the uplink shared data channel on at leastone subband based on an unsuccessful LBT procedure for the at least onesubband. The operations of 1525 may be performed according to themethods described herein. In some examples, aspects of the operations of1525 may be performed by a puncture module as described with referenceto FIGS. 6 through 9.

At 1530, the UE may transmit the uplink shared data channel via thesubset of the set of subbands excluding the at least one subband basedon the puncturing. The operations of 1530 may be performed according tothe methods described herein. In some examples, aspects of theoperations of 1530 may be performed by an uplink transmitter asdescribed with reference to FIGS. 6 through 9.

FIG. 16 shows a flowchart illustrating a method 1600 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The operations of method 1600 may beimplemented by a UE 115 or its components as described herein. Forexample, the operations of method 1600 may be performed by acommunications manager as described with reference to FIGS. 6 through 9.In some examples, a UE may execute a set of instructions to control thefunctional elements of the UE to perform the functions described herein.Additionally or alternatively, a UE may perform aspects of the functionsdescribed herein using special-purpose hardware.

At 1605, the UE may identify a set of subbands supported by a basestation in communication with the UE. The operations of 1605 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1605 may be performed by a subband manageras described with reference to FIGS. 6 through 9.

At 1610, the UE may receive an uplink grant for transmission of anuplink shared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof a first type for the subset of the set of subbands in thetransmission time interval. The operations of 1610 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1610 may be performed by an uplink grant receiver asdescribed with reference to FIGS. 6 through 9.

At 1615, the UE may receive, after receiving the uplink grant and withinthe transmission time interval, signaling that indicates one or moresubbands of the subset associated with an LBT procedure of a secondtype. The operations of 1615 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1615may be performed by a signaling receiver as described with reference toFIGS. 6 through 9.

At 1620, the UE may perform LBT procedures of the first type or thesecond type on the subset of the set of subbands based on the uplinkgrant and the signaling. The operations of 1620 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1620 may be performed by an LBT component as describedwith reference to FIGS. 6 through 9.

At 1625, the UE may transmit the uplink shared data channel via the oneor more subbands if each of the one or more subbands is associated witha successful LBT procedure of the second type, where the uplink shareddata channel is rate matched on the one or more subbands. The operationsof 1625 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1625 may be performed by anuplink transmitter as described with reference to FIGS. 6 through 9.

FIG. 17 shows a flowchart illustrating a method 1700 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The operations of method 1700 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1700 may be performed by acommunications manager as described with reference to FIGS. 10 through13. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1705, the base station may identify a set of subbands supported bythe base station in communication with a UE. The operations of 1705 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1705 may be performed by asubband identifier as described with reference to FIGS. 10 through 13.

At 1710, the base station may transmit an uplink grant for an uplinkshared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof the first type for the subset of the set of subbands in thetransmission time interval. The operations of 1710 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1710 may be performed by an uplink grant transmitteras described with reference to FIGS. 10 through 13.

At 1715, the base station may perform an LBT procedure for each of thesubset of the set of subbands. The operations of 1715 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1715 may be performed by an LBT module as describedwith reference to FIGS. 10 through 13.

At 1720, the base station may transmit, after transmitting the uplinkgrant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure. Theoperations of 1720 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1720 may beperformed by a signaling transmitter as described with reference toFIGS. 10 through 13.

FIG. 18 shows a flowchart illustrating a method 1800 that supports LBTfor uplink transmissions using multiple subbands in accordance withaspects of the present disclosure. The operations of method 1800 may beimplemented by a base station 105 or its components as described herein.For example, the operations of method 1800 may be performed by acommunications manager as described with reference to FIGS. 10 through13. In some examples, a base station may execute a set of instructionsto control the functional elements of the base station to perform thefunctions described herein. Additionally or alternatively, a basestation may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1805, the base station may identify a set of subbands supported bythe base station in communication with a UE. The operations of 1805 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1805 may be performed by asubband identifier as described with reference to FIGS. 10 through 13.

At 1810, the base station may transmit an uplink grant for an uplinkshared data channel via a subset of the set of subbands in atransmission time interval, the uplink grant indicating an LBT procedureof the first type for the subset of the set of subbands in thetransmission time interval. The operations of 1810 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1810 may be performed by an uplink grant transmitteras described with reference to FIGS. 10 through 13.

At 1815, the base station may perform an LBT procedure for each of thesubset of the set of subbands. The operations of 1815 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1815 may be performed by an LBT module as describedwith reference to FIGS. 10 through 13.

At 1820, the base station may transmit, after transmitting the uplinkgrant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type based on performing the LBT procedure. Theoperations of 1820 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1820 may beperformed by a signaling transmitter as described with reference toFIGS. 10 through 13.

At 1825, the base station may monitor each subband of the subset for theuplink shared data channel from the UE after transmitting the signaling.The operations of 1825 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 1825may be performed by a monitoring component as described with referenceto FIGS. 10 through 13.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may bedescribed for purposes of example, and LTE, LTE-A, LTE-A Pro, or NRterminology may be used in much of the description, the techniquesdescribed herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NRnetworks. For example, the described techniques may be applicable tovarious other wireless communications systems such as Ultra MobileBroadband (UMB), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, aswell as other systems and radio technologies not explicitly mentionedherein.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a CPU, an FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein may be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that may beaccessed by a general-purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that may be used to carry or store desired programcode means in the form of instructions or data structures and that maybe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of computer-readable medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an example step that is described as “based on condition A”may be based on both a condition A and a condition B without departingfrom the scope of the present disclosure. In other words, as usedherein, the phrase “based on” shall be construed in the same manner asthe phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “example” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

1. A method for wireless communications at a user equipment (UE),comprising: identifying a plurality of subbands supported by a basestation in communication with the UE; receiving an uplink grant fortransmission of an uplink shared data channel via a subset of theplurality of subbands in a transmission time interval, the uplink grantindicating a listen before talk (LBT) procedure of a first type for thesubset of the plurality of subbands in the transmission time interval;receiving, after receiving the uplink grant and within the transmissiontime interval, signaling that indicates one or more subbands of thesubset associated with an LBT procedure of a second type; and performingLBT procedures of the first type or the second type on the subset of theplurality of subbands based at least in part on the uplink grant and thesignaling.
 2. The method of claim 1, further comprising: puncturing theuplink shared data channel on at least one subband based at least inpart on an unsuccessful LBT procedure for the at least one subband; andtransmitting the uplink shared data channel via the subset of theplurality of subbands excluding the at least one subband based at leastin part on the puncturing.
 3. The method of claim 1, further comprising:performing LBT procedures of the second type on the one or more subbandsof the subset based at least in part on the signaling; and transmittingthe uplink shared data channel via each of the one or more subbandsassociated with a successful LBT procedure of the second type.
 4. Themethod of claim 1, further comprising: transmitting the uplink shareddata channel via the one or more subbands if each of the one or moresubbands is associated with a successful LBT procedure of the secondtype, wherein the uplink shared data channel is rate matched on the oneor more subbands.
 5. The method of claim 1, further comprising:performing LBT procedures of the first type on a first subband of thesubset based at least in part on the uplink grant; performing LBTprocedures of the second type on a second subband of the subset based atleast in part on the signaling; and transmitting the uplink shared datachannel via each of the first and second subbands associated with asuccessful LBT procedure.
 6. The method of claim 1, further comprising:performing LBT procedures of the first type on a first subband of thesubset based at least in part on the uplink grant; performing LBTprocedures of the second type on a second subband of the subset based atleast in part on the signaling; and transmitting the uplink shared datachannel via the first and second subbands if the first and secondsubbands are associated with a successful LBT procedure.
 7. The methodof claim 1, further comprising: performing LBT procedures of the firsttype on the subset of the plurality of subbands based at least in parton the uplink grant and a capability of the UE; and transmitting theuplink shared data channel via each subband of the subset associatedwith a successful LBT procedure.
 8. The method of claim 7, furthercomprising: transmitting the uplink shared data channel via the subsetof the plurality of subbands if each of the subset is associated withthe successful LBT procedure.
 9. The method of claim 1, furthercomprising: dropping the uplink shared data channel based at least inpart on an unsuccessful LBT procedure on at least one subband of thesubset.
 10. The method of claim 1, further comprising: receivingmultiple uplink grants via respective subbands of the subset of theplurality of subbands, wherein each of the multiple uplink grantscomprises resource allocation information for the uplink shared datachannel.
 11. The method of claim 10, wherein each of the multiple uplinkgrants comprises the same resource allocation information for the uplinkshared data channel via the respective subbands.
 12. The method of claim10, wherein each of the multiple uplink grants comprises differentresource allocation information for the uplink shared data channel. 13.The method of claim 10, further comprising: determining at least onesubband of the subset for transmission of the uplink shared data channelbased at least in part on the multiple uplink grants, wherein the atleast one subband corresponds to a subband over which one of themultiple uplink grants is received; and transmitting the uplink shareddata channel via the at least one subband, wherein the uplink shareddata channel includes uplink control information that indicates the atleast one subband used for transmission of the uplink shared datachannel.
 14. (canceled)
 15. The method of claim 1, wherein the uplinkgrant comprises a confidence indicator that indicates puncturinginformation for the subset of the plurality of subbands and which of thesubset of the plurality of subbands is available for the uplink shareddata channel.
 16. (canceled)
 17. The method of claim 1, furthercomprising: preparing the uplink shared data channel for transmission tothe base station via the subset of the plurality of subbands; puncturingthe uplink shared data channel on the one or more subbands based atleast in part on the signaling being received after preparing the uplinkshared data channel for transmission; and transmitting, based at leastin part on the puncturing, the uplink shared data channel via the subsetof the plurality of subbands associated with a successful LBT procedureand excluding the one or more subbands, wherein the uplink shared datachannel includes uplink control information indicating the subset of theplurality of subbands associated with the successful LBT procedure. 18.The method of claim 17, further comprising: receiving controlinformation indicating to the UE to include uplink control informationwith the uplink shared data channel, wherein the control informationcomprises radio resource control (RRC) information or downlink controlinformation (DCI).
 19. (canceled)
 20. The method of claim 17, whereinthe uplink control information includes subbands over which a punctureduplink shared data channel is transmitted or subbands used fortransmission of the uplink shared data channel.
 21. The method of claim1, further comprising: transmitting the uplink shared data channel viaeach subband of the subset associated with a successful LBT procedure,wherein the uplink shared data channel includes uplink controlinformation indicating each subband of the subset associated with thesuccessful LBT procedure.
 22. The method of claim 21, furthercomprising: determining a set of resources of each subband for theuplink control information, wherein the set of resources is based atleast in part on one or more subbands of the subset subject topuncturing according to an unsuccessful LBT procedure.
 23. The method ofclaim 22, further comprising: evenly distributing uplink controlinformation across each subband, wherein the uplink control informationcomprises information other than information indicating each subband ofthe subset associated with the successful LBT procedure.
 24. The methodof claim 21, further comprising: determining a set of resources of eachsubband for the uplink control information based at least in part on anumber of the subset of the plurality of subbands indicated in theuplink grant, a number of subbands used for transmission of the uplinkshared data channel, a number of subbands associated with the LBTprocedure of the second type, all of the plurality of subbands supportedby the base station for communications with the UE, or any combinationthereof.
 25. The method of claim 21, further comprising: multiplexinguplink control information with the uplink shared data channel via atleast one subband independent of a number of subbands used fortransmission of the uplink shared data channel, wherein a same number ofsymbols for the at least one subband is used for multiplexing the uplinkcontrol information irrespective of other subbands.
 26. (canceled) 27.The method of claim 1, further comprising: preparing the uplink shareddata channel for transmission to the base station via the subset of theplurality of subbands associated with a successful LBT procedure basedat least in part on the signaling, wherein the signaling is receivedbefore a threshold time for preparation of the uplink shared datachannel; and transmitting the prepared uplink shared data channel. 28.The method of claim 1, further comprising: receiving the signaling aftera threshold time for preparation of the uplink shared data channel; andtransmitting the uplink shared data channel irrespective of thesignaling.
 29. (canceled)
 31. The method of claim 1, wherein: the LBTprocedure of the first type comprises a category 4 LBT procedure; andthe LBT procedure of the second type comprises a category 2 LBTprocedure.
 32. A method for wireless communications at a base station,comprising: identifying a plurality of subbands supported by the basestation in communication with a user equipment (UE); transmitting anuplink grant for an uplink shared data channel via a subset of theplurality of subbands in a transmission time interval, the uplink grantindicating a listen before talk (LBT) procedure of a first type for thesubset of the plurality of subbands in the transmission time interval;performing an LBT procedure for each of the subset of the plurality ofsubbands; and transmitting, after transmitting the uplink grant andwithin the transmission time interval, signaling that indicates one ormore subbands of the subset associated with an LBT procedure of a secondtype based at least in part on performing the LBT procedure. 33-43.(canceled)
 44. An apparatus for wireless communications at a userequipment (UE), comprising: means for identifying a plurality ofsubbands supported by a base station in communication with the UE; meansfor receiving an uplink grant for transmission of an uplink shared datachannel via a subset of the plurality of subbands in a transmission timeinterval, the uplink grant indicating a listen before talk (LBT)procedure of a first type for the subset of the plurality of subbands inthe transmission time interval; means for receiving, after receiving theuplink grant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type; and means for performing LBT procedures ofthe first type or the second type on the subset of the plurality ofsubbands based at least in part on the uplink grant and the signaling.45. (canceled)
 46. A non-transitory computer-readable medium storingcode for wireless communications at a user equipment (UE), the codecomprising instructions executable by a processor to: identify aplurality of subbands supported by a base station in communication withthe UE; receive an uplink grant for transmission of an uplink shareddata channel via a subset of the plurality of subbands in a transmissiontime interval, the uplink grant indicating a listen before talk (LBT)procedure of a first type for the subset of the plurality of subbands inthe transmission time interval; receive, after receiving the uplinkgrant and within the transmission time interval, signaling thatindicates one or more subbands of the subset associated with an LBTprocedure of a second type; and perform LBT procedures of the first typeor the second type on the subset of the plurality of subbands based atleast in part on the uplink grant and the signaling.
 47. (canceled)